Chemical chaperones for Niemann-Pick C disease

描述（由申请方提供）：NPC 1疾病是一种严重的溶酶体变性，其中胆固醇和其他脂质从内体/溶酶体（E/L）系统中的排出是有缺陷的，导致神经变性和过早死亡。NPC疾病的主要形式NPC 1的蛋白质是已知的。初步表征表明，NPC 1可能作为一种脂质渗透酶的膜上的晚期内体。然而，NPC 1的确切功能及其在NPC疾病发病机制中的作用仍然难以捉摸，并且目前没有用于这种衰弱性疾病的治疗形式。我们假设许多NPC 1突变是致病的，因为突变蛋白不能从内质网成熟，因此不能靶向晚期核内体。药理学相关的化学分子伴侣最近在增强突变蛋白质成熟从而部分挽救蛋白质活性方面显示出巨大的前景。我们将首先建立一种检测突变NPC 1蛋白成熟和ER退出的方法。其次，我们将使用我们的内部高通量设施，以确定化学分子伴侣，可以拯救突变NPC 1蛋白。然后将在基于细胞的测定中评估这些分子，以确定NPC表型校正的水平，并评估其在未来动物和NPC 1患者研究中的效用。小分子伴侣的成功鉴定将为这种方法提供“原理证明”，并为NPC 1和其他由膜蛋白错误折叠引起的破坏性神经系统疾病的研究提供新的途径。

DESCRIPTION (provided by applicant): NPC1 disease is a severe lysosomal lipidosis in which the egress of cholesterol and other lipids from the endosomal/ lysosomal (E/L) system is defective, leading to neurodegeneration and premature demise. The protein responsible for the major form of NPC disease, NPC1 is known. Preliminary characterization suggests that NPC1 may act as a lipid permease on the membranes of late endosomes. However, the exact function(s) of NPC1 and its role in NPC disease pathogenesis remain elusive and no form of treatment for this debilitating disorder is currently available. We hypothesize that many NPC1 mutations are disease causing due to the fact that the mutant proteins are unable to mature from the endoplasmic reticulum and are thus unable to be targeted to the late endosome. Pharmacologically relevant chemical chaperones have shown great promise recently in enhancing mutant protein maturation and thus partial rescue of protein activity. We will first establish an assay for detecting the maturation and ER exit of mutant NPC1 proteins. Second, we will use our in-house high throughput facility to identify chemical chaperones that can rescue mutant NPC1 proteins. These molecules will then be evaluated in cell-based assays to determine the level of NPC phenotype correction and assess their utility in future animal and NPC1 patient studies. Successful identification of small molecule chaperones will provide "Proof-of-principle" for this type of approach, and a new avenue of research for NPC1 and other devastating neurological disorders caused by membrane protein misfolding.